30天-6°头低位卧床对男性牙菌斑中变形链球菌数量的影响

Effects of 30 d- 6° Head-down Bed Rest on Contents of Streptococcus Mutans in Bacterial Plaques of Men

目的观察30天-6°头低位卧床(head-down bed rest,HDBR)对男性志愿者牙菌斑中变形链球菌数量的影响。方法对21名健康男性志愿者按照5个不同的时间点分组:对照组———卧床前适应期第7天(pre-HDBR-7)、卧床第10天(HDBR-10)、第20天(HDBR-20)、第30天(HDBR-30)、卧床后恢复期第7天(post-HDBR-7);在5个时间点分别对其下颌第一磨牙舌侧平滑面菌斑进行采样,应用TaqMan real-time PCR的方法,对菌斑中变形链球菌进行定量检测,组间比较分析。结果与对照组相比,第10天变形链球菌数无显著变化;第20天组菌数差异显著(P<0.05);第30天组菌数有显著性差异(P<0.05);恢复期组菌数无统计学差异。结论在30天-6°头低位卧床中,随着时间的增加,牙菌斑中变形链球菌数量增加,提示龋病、牙周病的风险也随之增加,其机制尚需进一步研究。

Objective To investigate the effects of 30 d -6° head-down bed rest （HDBR） on the contents of streptococcus mutans（SM） in bacterial plaques of 21 male volunteers. Methods The plaques were collected from lingual surface of 6th lower molars, before HDBR （ pre-HDBR-7）, on the 10th （ HDBR-IO）, 20th （ HD- BR-20） ,30th day of HDBR（HDBR-30）, and the 7th day after HDBR （post-HDBR-7） respectively. The contents of SM in plaques were detected with Taq Man real-time PCR and the data were statistically analyzed and compared. Results As compared with pre-HDBR-7 group, the content of SM were： no significant differ- ence in HDBR-10 group, significant difference in HDBR-20 group （ P 〈 0.05 ）, significant difference （ P 〈 0. 05 ） in HDBR-30 group and no significant difference in post-HDBR-7 group. Conclusion HDBR for 30 d at - 6° may increase the content of SM in bacteroal plaques along time increased. It means that the risk of peridon- tal disease and dental cariosus may be enhanced. But the mechanism needs further study.